FP, I like the level of whiteness you are achieving.
With your Bentobox, if you don't like how it looks or sits at the front of your top tube, try it at the other end of you top tube up against your seat post. I've seen quite a few people do this. Aero wise it would be slightly better as your knees and thighs are disturbing whatever aero drag the Bentobox may catch. Functionally, I think it's not a good spot. But try it if you like, just to see.
Honestly, the speeds us age groupers are doing on our Tri bikes, the position of biddons and Bentobox's is negligible in the overall drag coefficient of our bikes. The biggest gains to be made are with the human riding the bike and the position the human is in whilst riding. That's worth a thread on its own.